Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; The Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Translational Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark. Electronic address: epwi@sund.ku.dk. Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; The Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Translational Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark. Department of Radiology, Herlev University Hospital, Herlev 2730, Denmark. The Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Metabolic Genetics, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark. Department of Endocrinology, Hvidovre University Hospital, Hvidovre 2650, Denmark. The Children's Obesity Clinic, Department of Pediatrics, Holbæk University Hospital, Holbæk 4300, Denmark. Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; The Novo Nordisk Foundation Center for Basic Metabolic Research, Section for Translational Metabolic Research, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark. Electronic address: torekov@sund.ku.dk.